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(No Model.) 2 Sheets-Sheet 1.

M. KIRKER.

MANUFACTURE OF DRAW BARS. No. 351,382. Patented Oct. 26, 1886.

Pia. 1-

(No Model.) 2 Sheets-Sheet 2.

M. KIRKER.

MANUFACTURE OF DRAW BARS.

Patented Oct. 26, 1886.

No. 351,382. FIG-5,.

MUTLEEE E5 ATLVETITUR- UNITED STATES PATENT OFFICE.

MILTOL KIRKER, OF PITTSBURG, PENNSYLVANIA, ASSIGNOR OF ONE-HALF TO JOSEPH D. LONG, OF SAME PLACE.

MANUFACTURE OF DRAW-BARS.

SPEQIFICATION forming part of Letters Patent No. 351,382, dated October 26, 1 886.

Application filed August 2, 1886. Serial 'No. 209,756. (No model.) I

T aZZ whom it may concern:

Be it known that I, MILTON KIRKER, of Pittsburg, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in the Manufacture of Draw-Bars; and I do hereby declare the following to be a full, clear, and exact description thereof.

My invention in'the manufacture of drawro bars consists in a series of forging and upset ting operations, whereby a solid draw-bar is formed in a single piece out of a-bar of iron or steel.

It also consists in the machines by which some of these operations are performed.

To enable others skilled in the art to make and use my invention, I will now describe it by reference to the accompanying drawings, in which Figure 1 is a view of the original bar. Fig. 2 is a view ofthe same after the first step. Fig. 3 is a longitudinal section of the dies and plunger by which the second step is performed. Fig. & shows the same dies and plunger separated, the top die being inverted, and the position of the piece when placed in the dies to be operated on being illustrated in connection with the lower die. Fig. 5 is a view of the piece after being operated on by the dies and plunger, shown in Fig. 4. Fig. 6 is a longitudinal plansection of the dies and plunger by which the third step is performed. Fig. 7 shows the same dies and plunger separated, the top die being inverted. Fig. Sis a view of 5 the completed draw-bar.

Like letters of reference indicate like parts in each.

In practicing my'iuvention, I take a rectangular bar, a, of iron or steel, and forge down 40 or otherwise form one end of it into a pin, 1),

which terminates at a square or abrupt shoulder, 0. The other end of the bar is drawn down into a narrow form, as at (I, one side or edge of the bar being made straight from the shoulder c to the end, as at c. This bar is shown in Fig. 2. The next step is performed in a die, f, which has a longitudinal recess, 2, of the same width as the bar in its face. The depth of the recess is half the thickness of the bar, as shown by dotted lines in Fig. 3, ex-

cept at the front end of the die, where it is much deeper, as at 3, and the shallow and deep portions of said recess are united by a shoulder, t. An upper die, g, of the same form as the dief, is used in conjunction therewith. Then these two dies act on the bar a, they inclose it, their shallow recesses 2 clamping and holding it, while their deep recesses 3 form a matrix, into which a portion next to the pin b is upset against the shoulders 4. A plunger, 71, of proper size to enter the matrix, is used with these dies. The plunger has a hole, 5, extending longitudinally into it from its front end, of sufficient size and depth to receive the pin '1), and at the rear end of the hole 5 it has a transverse slot, 6, which enables the pin to be pried or wedged out, if it should stick. The bar a is first'heated at the, base of the 'pin 1) and then placed in the dies f g, with its shouldered end projecting into 7cthe matrix 3 beyond the shoulders i, and its pin projecting beyond the open ends of the dies, as shown in Fig. 4, and then the plunger IL advances and enters the open end of the matriX 3, the pin 2) entering the hole 5 of the plunger. The end of the plunger delivers the proper number of blows on the shoulder a of the bar, upsetting the end of the bar against the shoulders 4 of the dies and filling the inner end of the matrix, thereby forming a solid 8.) square or other shaped boss, '17, at the base of the pin, as shown in Fig. 5. The bar is next submitted to the action of the devices shown in Figs. 6 and 7. Here are two dies, at a, of similar shape, each having a shallow groove, 8 5 6, for receiving the narrow end (I of the bar, and at the front end otthis groove is a wider recess, 7, of the same depth, one side, 8, of which extends farther in than the other side, 9.

At the junction of the groove 6 with the 0 side 9 of the wide recess 7 is a curved shoulder, 10, the shape of which is the counter part of the inner curve of the hook it, which is to be formed on the end of the draw-bar.

A plunger, 0, is used with these dies.

of the same width as the recess 7, so as to move therein as in guides, and is provided with a long projecting end, 11, on one side, which works in the side 8 of the recess 7, and a short end, 12, which works in the side 9, and the roe It is 5 ends 11 and 12 are connected by an intermediate curved or concave surface, 13, which is the counterpart'of the outer curve of the hook is of the draw-bar. The end of the drawbar is first heated, and is placed in the dies in? nin the position shown by dotted lines in Fig. 7, where it is firmly held by the dies, or is supported from behind, so that it will not be displaced by the action of the plunger.- It is then struck the required number of blows by the plunger, to upset the end and form a hook,

7c, thereon of the shape of the matrix formed between the two curved surfaces 10 and 13, as shown in Fig. 6. The result of these successive operations is the draw-bar shown.in

.Fig. 8, formed in a single piece from the rolled bar a, the pin '1), boss t, body (I, and hook it being integral, whereby welding is avoided and greater strengthbbtained. The operation is simple and performed with an economy of labor. I The tools are comparatively not eX- pensive.

I do not limit myself to the particular order of steps named,'nor to the particular form of draw-bar made, nor to the specific form and construction ofdies and plungers described, because these things are immaterial and may be 1 varied, so long as the fundamental steps and constructions set forth' in the claims are retained. It will be apparent that the hook it may be formed by bending or by stamping it out in drop-dies, instead of being formed by upsetting, as described; and therefore I do not in my first claim limit myself to forming it by upsetting, as described, although I believe that method to be the best, and consequently preterit. In this method of making draw-bars out of a single bar I save fully one-half, the" number of heats necessary in any prior method known to me, and more than half the labor. The bar is preferably rolled to form.

What I claim as my invention, and desire to secure by Letters Patent, is

1. An improvement in the art of making draw-bars, which consists in forming a pin on one end of the bar and then upsetting the bar at the base of the pin to forma boss or shoulder on the bar, substantially as and for the purposes described.

2. The method of making draw-bars, which consists in forming a pin on one end of the bar, upsetting the bar at the base of the pin to form a boss or shoulder, and upsetting the other end of the bar to form a hook, substantially as and for the purposes described.

3. A pair of dies for use in the manufacture of draw-bars, having' a matrix at one end capable of receiving a plunger, and a shallower recess at the rear of the matrix for receiving the body of the blank, in combination with a plunger perforated to work over the pin of the draw-bar, for upsetting the barin the matrix to form a shoulder or boss at the base of the pin, substantially as and for thepurposes described.

4. A pair of dies for use in the manufacture of draw-bars, having a recess for receiving the end of the draw-bar, and a matrix at the end of the recess provided with a forming-surface upon which to upset the bar to form a hook, in combination with a plunger having a concave end, by which the end of the bar is up set and formed into a hook upon the forming surface of the die, substantially as and for the purposes described.

In testimony whereof I have hereunto set my hand this 21st day of July, A. D. 1886';

MILTON KIRKER \Vitnesses:

WV. B. CORWIN, THOMAS B. KERR. 

